Bathroom scale



Jan. 26, 1954 M. A. PROVENZANO BATHROOM SCALE Original Filed March 10, 1947 Patented Jan. 26, 1954 ers? UN I'T ED STATES PATEQN OFFICE BATHROOM. SCALE Mike A. Provenzano, Rockford, 111., ass'ignor to The fBrea'rley Company, Rockford, 111., :a corporationnflllinois Original applicationMarch 10, "19.47, Serial "No.

733,582. Divided and this application December .4,"1950,*S,eria'l No. 199,019

scale of stamped sheet metal construction for lightness, durability, and economy.

The principal object of this invention is to provide punched sheet metal hangers or fulcrum bearings for support of the platform on the wishbone levers and for fulcrum support of the one wishbone lever'on'the'other. Hangers of thisgeneral type are wellknown, as shown, for example, Sutton Patent 2,293,572, issued August 18, 1942, but they were heretofore of 'cast construction'and required machining of the knife-edge portions, thus making these parts too expensive, not to mention the fact that it was very difiicult to produce the knife-edges in coplanar relationship by that method. Furthermore, the knife-edges thus formed were not durable and COLll'dlb'S easily dulled and could not be produced to the'desired sharpness in the first place, due to the heavy cast construction. In accordance with my invention, the generally U-shaped hangers are in the form of sheet metal punchings having outwardly .projecting fulcrum portions on the upper endso'f the arms of the U, on the bottom of which knife-edge fulcrums are provided by bevelling the edges of these projecting portions both one :way, another knife-edge fulcrum being provided between the arms of the U on top of the cross-portion by bevelling the edge of this portion the same way, thereby insuring knife edges which are not only of the desired sharpness but truly in coplanar relationship, inasmuch'as they are all 'inthe same plane face of the member. The punchings are subjected to heavy pressure along their edges between dies to provide the knife edges as distinguished from a machining operation, thus pro ducing edges which are more accurate in-quantity production as to alignment. The heavy die pressure also gives the edges work hardness by compaction of the metal which makes f-or'longer'wear and the nunchings are finall'ysuitably heat treated for further hardening to give still longer life.

The invention is illustrated in the accompanying drawings, in which- Fig. 1 is a plan view of a bathroom scale made in accordance with .rny invention, with the platform removed, but indicating in dot and dash lines the location of the fourlegs of the platform for support of the platform by means .of hangers on the wishbone levers;

Figs. 2 and 3 are enlarged sectional details on the lines 2-2 and "3-3 at Fig. 1, looking in the direction ofthe arrows;

Fig. 4 is a sectional detail on line 'i-- i of'Fig. 1, and

Fig. 5 is a perspective View of one of the hangers shown in Figs. 2 and 3.

The same reference numerals are applied to corresponding parts throughout the views.

Referring .to the drawings, the reference numeral i6 designates the generally rectangular sheet metal base of a bathroom scale on which a generally rectangular sheet metal platform H is supported onsaid base through the medium of the lever mechanism of my invention, indicated generally by the reference numeral 58. The latter, generally speaking, consists of a small U- shaped spider or wishbone lever it, and a "large generally triangular-shaped spider or wishbone lever 29, the two lovers being interconnected by a hanger 2!. It is common practice to fulcrum the'large lever at one end onthelbase and to support .the other end of the lever on a coiled tension spring, like that indicated .at 2?, which is suitably suspended in the dial supporting frame 23 that is mounteolon the front end of the base, the spring being supported by means of a screw 2i andadjusting nut .2'5,,so that the scale can be set back to zero if it gets out of adjustment. Ihe small lever I Bis supported at one end on the'base and .at its-other end-on the large lever '25 so as to transfer its load to the large lever, the platform being supported at the front end on the small lever and at the rear'endon the large lever. Two

arms 25 project upwardly from the front corners ofthebase to support the lever l9, and two arms 2! project upwardly from the rear corners of the base for support of the lever 2 Two legs it project downwardly from the corners of the front end of the platform to rest on the lever it, and two legs 29 project downwardly from the corners of the rear-end of the platform to rest on the lever 20. The weight is indicated on a dial 35 rotatably mounted in the frame 23 and visible through a window 3! in the top of the dial housing 32 and operable by a pinion 33 meshing with a rack 34 that is suitably guided in the frame 23 for reciprocatory movement vertically and rests at its lower end on the front end of the lever it, said rack being arranged .to gravitate in proportion to the deflection ofthe levers i9 and 2% under load. Two coiled tension springs 35 are connected at their opposite ends to and stretched between the platform ll and base it to hold the parts in assembled relation and permit picking up the scale y its platform.

In accordance with the disclosure in t e parent application, the spiders or levers l9 and 20, instead of being of heavy cast iron construction, or of welded steel construction, have the bodies 36 and 31 thereof each made from a single piece of sheet metal formed between dies to the flanged and ribbed forms shown. Thus, the lever l9 has downwardly projecting marginal flanges 38 and 39 on the inner and outer peripheries for stiffness and strength, these flanges being integrally interconnected at the ends of the lever by flanges 40 for maximum strength and rigidity. The major portion of the web 4| of this lever is depressed to define channel shaped ribs 42 and 43 along the inner and outer peripheries for further reinforcementof the lever to reduce to a minimum distortion under load and avoid likelihood of the lever getting bent out of shape. In a similar manner, lever 2|] has a continuous downwardly projecting marginal outer flange 44 v and has a triangular shaped opening 45 in the center thereof defined by a downwardly projecting continuous flange 45 to lend stiffness and strength, and longitudinally extending ribs 41 are struck upwardly from the web 48 to reinforce the lever 26 in the region where heavy strains are concentrated by reason of the lever l9 transmitting its load to lever 21.! at this point. It is clear in Fig. 1 that the close spacing of flanges 44 and 49 and ribs 41 in this region, plus the fact that the marginal flange 44 is rather abruptly widened on both sides of lever 2|] at this region, as shown at 56, make for the necessary strength and rigidity so that lever 26 will not be flexed too much under load and ultimately get bent out of shape. The flange 49 is a continuous rectangular flange defining a rectangular opening 5| provided in the forwardly extending arm 52 on lever 26 through which the lower portion of the dial 36 projects. The flange 49 cooperates with marginal flange 44 to form a channel section on both sides of the arm 52 so that the arm has ample strength and rigidity even though so much of it is cut away to provide the dial opening 5!. These two channels, incidentally, give enough strength to make it feasible to have the arm 52 of rather small width on both sides of the dial, as best appears in Fig. 1, so that the width of dial frame 23 can be reduced to a minimum, thus permitting use of a dial housing 32 of narrow width so that more foot room is left on the platform I! on opposite sides of the dial housing. The flange 44 is notched at two points on the rear end of lever 20, as shown at 55 in Fig. 1, in register with the upwardly reaching arms 21 and has bevelled straight edges 56 filed or pressed on the upper ends of these notches to provide the equivalent of the knife edge fulcrums usually machined on the other types of levers, for fulcrum engagement in the bottoms of V -notches 51 provided in the upper ends of arms 21. In like manner bevelled straight edges 58 are provided on the end flanges 40 of lever I9 in notches 59 for fulcrum engagement in the bottoms of V-notches 60 provided in the upper ends of arms 26.

The web portion 4| of lever 19 has openings 6| and 62 punched therein near the front end of each arm of the lever, the metal from these openings being bent downwardly on one side of the openings to provide two spaced parallel vertical ears 63 on which the improved U-shaped hangers or fulcrum bearings 64, forming the subject matter of this application, for fulcrum support of the front end of the platform, are rockably mounted by their aligned outwardly projecting end portions 65, the downwardly 011- set middle portions 66 being arranged to engage in the V-notches 66 provided in the lower ends of the legs 28 on the front end of the platform, as clearly shown in Fig. 3. The cars 63 have V-notches 61 provided therein to receive the bevelled edges 68 on the bottom of end portions 65 of hangers 64, and there is a bevelled edge 69 on top of the offset middle portion 66 to enter construction, compared with castings, is cheaper but better, because, when the three bevelled edges 68 and 69 are produced tapering to the same face of the piece, as shown in Fig. 5, there can be no room for doubt that these edges are all in accurate coplanar relationship, whereas it was a very diflicult matter to obtain such coplanar relationship in cast hangers, like those shown in Sutton Patent 2,293,572, in quantity production. The compression of the metal at the edges 68 and 69 makes for hardness and longer wear without a hardening operation. The web 4| is cut away on diametrically opposite sides of openings 6|, as indicated at 10, as con tinuations of the slots in the ears 63 terminating in the V-notches 61, to provide clearance for the arms 65 and permit the hangers 64 to be dropped into place in notches 61 from above the lever l9. In a similar way, ears 1| having V-notches 12 therein are bent downwardly from the web 48 of lever 20 on opposite sides of openings 13, the openings 13 in this case having diametrically opposed side extensions 14 to allow passage of arms 65 of hangers 54, the bevelled edges 68 of these hangers resting in notches I2 and the bevelled edges 69 being entered in V-notches 15 provided in legs 29 on the rear end of the platform.

The web portion of lever I9, as best shown in Fig. 4, has an ear 16 bent downwardly therefrom at the middle of the rear cross-portion to rest on the hanger 2! and thus transmit the load carried by the lever Hi to lever 26. The hanger 2| is bent from a short length of stiff wire of round section to provide coaxially aligned trunnion ends H and a straight middle crank pin portion 18 in offset parallel relation to the ends. The web portion 48 of lever 20 has an opening 19 punched therein for projection downwardly therein of the middle crank pin portion 18 of the hanger 2| and the ear 16, which has a V- notch 86 with a semi-circular crotch to fit on the crank pin portion. The trunnion ends 11 of hanger 2| are rotatably supported on top of the web portion 46 of lever 20 and are held against lateral displacement by spaced lugs 8| bent upwardly from the web 48 at opposite ends of the opening 19. A downwardly projecting lug 82 is also provided on the lever I9 at the middle of the back of the cross portion, as an integral extension from flange 39, which projects freely through a slot 83 provided in the web 48 behind and parallel to the opening 19, the lower end portion of the lug being bent rearwardly, as clearly appears in Fig. 4, to limit upward movement of the rear end of lever I9 and thereby prevent disassociation of the ear l6 and hanger 2| in event a person causes the levers l9 and 26 to oscillate more rapidly than usual in normal operation, as, for example, by resting only one foot on the platform and depressing the same and quickly releasing the pressure. The lever I9 is assembled in the scale by first entering lug 82 in slot 83 and then lowering the front ends of the arms to rest on arms 23. This portion of the scale obviously involves the same kind of inexpensive punching and forming operations as in the provision of the ears S3 and H previously described.

It is believed the foregoing description conveys a good understanding of the objects and advantages of my invention. The appended claims have been drawn to cover all legitimate modifications and adaptations.

I claim:

1. As an article of manufacture, a swingable fulcrum bearing for use in scales and the like, said bearing being constituted by a piece of sheet metal having a generally U-shape with aligned outwardly reaching portions at the outer ends of the arm portions of the U, said outwardly reaching portions being provided with knife edges 25 in axial alignment on their lower faces and which are adapted to carry the bearing in a vertical plane upon a support for swinging movement about an axis coincident with said knife edges, and with the cross portion of the U having on its upper face a knife edge co-planar with and facing the other said knife edges, all of said knife edges being formed by cold working between dies under heavy pressure whereby the metal which constitutes such edges is compacted to enhance the work hardness of such edges.

2. A swingable fulcrum bearing as in claim 1 wherein all of said knife edges lie in the plane of one and the same face of the sheet metal.

MIKE A. PROVENZANG.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,293,572 Sutton Aug. 18, 1942 FOREIGN PATENTS Number Country Date 190,315 Great Britain Dec. 21, 1922 

